Last Modified: 05-13-2024 6.11:8.1.0 Doc ID: RM1000000028D8L
Model Year Start: 2023 Model: GR Corolla Prod Date Range: [11/2022 -           ]
Title: BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM (for Gasoline Model with Electric Parking Brake System): TRAC does not Operate; 2023 - 2025 MY Corolla Corolla Hatchback GR Corolla [11/2022 -        ]

TRAC does not Operate

DESCRIPTION

When TRAC or VSC is operating, the skid control ECU (brake actuator assembly) blinks the slip indicator light to inform the driver that slippage occurred.

When in VSC off mode, or TRAC and VSC are disabled, the multi-information display in the combination meter assembly displays "Traction Control Turned Off" and the VSC OFF indicator light illuminates to inform the driver.

When a communication malfunction with the ECM is detected, TRAC and VSC are disabled. Also when the system is malfunctioning, TRAC and VSC are disabled and the indicator lights of related systems illuminate.

PROCEDURE

1.

BRAKE PROBLEM CHECK

(a) Check if the slip indicator light was illuminated when TRAC did not operate.

OK:

The slip indicator light was illuminated.

HINT:

When a DTC is stored, the slip indicator light is illuminated and TRAC does not operate due to the fail-safe function.

(b) Check the operation condition of the VSC OFF switch (combination switch assembly) when TRAC did not operate.

OK:

The VSC OFF switch (combination switch assembly) had been operated to turn off TRAC when TRAC did not operate.

HINT:

When the multi-information display in the combination meter assembly displays "Traction Control Turned Off", TRAC does not operate.

OK

END

NG

2.

CHECK DTC

(a) Connect the GTS to the DLC3.

(b) Turn the ignition switch to ON.

(c) Read the DTCs following the prompts on the GTS. Enter the following menus: Chassis / Brake/EPB / Trouble Codes.

Chassis > Brake > Trouble Codes

(d) Check the DTCs (electronically controlled brake system) that are output.

Result

Proceed to

DTCs are not output.

A

Electronically controlled brake system DTCs are output.

B

B

REPAIR CIRCUITS INDICATED BY OUTPUT DTCS 2023 MY Corolla Corolla Hatchback GR Corolla [11/2022 - 03/2023]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM (for Gasoline Model with Electric Parking Brake System): DIAGNOSTIC TROUBLE CODE CHART 2023 MY Corolla Corolla Hatchback GR Corolla [03/2023 - 08/2023]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM (for Gasoline Model with Electric Parking Brake System): DIAGNOSTIC TROUBLE CODE CHART 2024 - 2025 MY Corolla Corolla Hatchback GR Corolla [08/2023 -        ]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM (for Gasoline Model with Electric Parking Brake System): DIAGNOSTIC TROUBLE CODE CHART

A

3.

CHECK VEHICLE

(a) Operate the VSC OFF switch (combination switch assembly) and check that the multi-information display in the combination meter assembly displays "Traction Control Turned Off" and the VSC OFF indicator light illuminates in accordance with the operation of the switch.

OK:

The multi-information display in the combination meter assembly displays "Traction Control Turned Off" and the VSC OFF indicator light illuminates in accordance with the operation of the switch.

NG

INSPECT VSC OFF SWITCH CIRCUIT

OK

4.

PERFORM DEALER MODE (SIGNAL CHECK) INSPECTION (SPEED SENSOR CHECK)

(a) Connect the GTS to the DLC3.

(b) Turn the ignition switch to ON.

(c) Enter the following menus: Chassis / Brake/EPB / Utility / Signal Check.

(d) Using the GTS, perform a Dealer Mode (Signal Check) inspection sensor check and check that speed sensor Dealer Mode (Signal Check) inspection items change from incomplete to complete.

Click here 2023 - 2025 MY Corolla Corolla Hatchback GR Corolla [11/2022 -        ]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM (for Gasoline Model with Electric Parking Brake System): TEST MODE PROCEDURE

Chassis > Brake/EPB > Utility

Tester Display

Signal Check

OK:

Speed sensor Dealer Mode (Signal Check) inspection items change from incomplete to complete.

NG

INSPECT AND REPAIR MALFUNCTIONING SPEED SENSOR CIRCUIT

OK

5.

PERFORM OPERATION CHECK DRIVING

(a) Operate the VSC OFF switch (combination switch assembly) and check that the system is not in TRAC off mode or VSC off mode.

(b) Check that no DTCs are output and that each warning light is not illuminated.

(c) Start off the vehicle on a low friction surface and check that TRAC operates when attempting to make the drive wheels slip.

OK:

TRAC operates when slip occurs when starting off.

NOTICE:

  • Even when the system is normal, VSC may not operate when the vehicle speed is low or TRAC may not operate due to a malfunction. Make sure that only the drive wheels slip during the procedure.
  • When confirming that the slip indicator light blinks, do not slip the drive wheels longer than necessary. Whether TRAC operated or not can be checked by reading the Vehicle Control History (RoB) when the system operated.

    Click here 2023 - 2025 MY Corolla Corolla Hatchback GR Corolla [11/2022 -        ]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM (for Gasoline Model with Electric Parking Brake System): VEHICLE CONTROL HISTORY (RoB)

  • Pay attention to your surroundings when performing the procedure and depress the accelerator pedal with caution.
OK

USE SIMULATION METHOD TO CHECK

NG

REPLACE BRAKE ACTUATOR ASSEMBLY